Fermented or fruit based beverages in particular are often cloudy or hazy. The haze in fermented beverages is due to the presence of protein and tannin molecules, along with yeast cells.
Due to consumer preference, it is often desirable to clarify the haze from such beverages. Additionally, clarification removes molecules which could aggregate and block processing equipment. In wine and some beers, acceptable levels of clarification may occur by standing the beverage over an extended period to allow agents producing the haze to settle. However, in the case of many beverages, particularly ales, lagers and fruit juices, where shelf life is not particularly long, it is necessary to effect rapid clarification to speed up delivery of the product to the consumer.
Brewers aim for short production times and limited inventories. Various additives or finings agents are generally used to enhance solids separation in beer streams.
Finings agents are used to associate with proteinaceous material in the beverage and form a precipitate which rapidly falls to the bottom of the storage vessel as a dense floc which then can be removed.
Isinglass is a fish bladder collagen preparation, which is added to storage beer to promote beer clarity and so improve filtration performance. Auxiliary finings agents such as silicates or polysaccharides may be used together with Isinglass.
Recently it became mandatory to label beer for the presence of fish-derived ingredients because of allergy issues. Bovine-sourced replacement collagens, need not carry the same warning. However bovine products have negative sentiment in the market because of Bovine Spongiform Encephalopathy (BSE) disease and may, at best, be considered short-term replacement finings agents. There are no known non-collagen alternatives that are as cost effective as Isinglass. Brewers are anxious to find an acceptable Isinglass replacement.
Another problem with using Isinglass as a finings agent for wine is that Isinglass takes out polyphenols in the wine and therefore may alter some of the characteristics of the wine.
Competitive finings agents such as Silicasol™ and carrageenans provide variable results according to the industry and may have drawbacks—fluffy bottoms and contamination of yeast residues.
It is an aim of the present invention to provide a reliable Isinglass alternative for use in clarifying beverages, particularly fermented beverages such as beer and wine.
It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents forms part of the common general knowledge in the art, in Australia or in any other country.